Question

t^2+2t-15=0

solve.

Answer 1

(t-3)(t+5)
t = 3, -5

Answer 2

t^2+2t-15=0


t^2+5t-3t-15=0


(t^2+5t)+(-3t-15)=0


t(t+5)+(-3t-15)=0


t(t+5)-3(t+5)=0


(t-3)(t+5)=0


t-3 = 0 or t+5 = 0


t = 3 or t = -5